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arXiv · 0707.1341

Coherence of an optically illuminated single nuclear spin qubit

Liang Jiang·M. V. Gurudev Dutt·Emre Togan·Lily Childress·Paola Cappellaro·Jacob M. Taylor·Mikhail D. Lukin
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Abstract

We investigate the coherence properties of individual nuclear spin quantum bits in diamond [Dutt et al., Science, 316, 1312 (2007)] when a proximal electronic spin associated with a nitrogen-vacancy (NV) center is being interrogated by optical radiation. The resulting nuclear spin dynamics are governed by time-dependent hyperfine interaction associated with rapid electronic transitions, which can be described by a spin-fluctuator model. We show that due to a process analogous to motional averaging in nuclear magnetic resonance, the nuclear spin coherence can be preserved after a large number of optical excitation cycles. Our theoretical analysis is in good agreement with experimental results. It indicates a novel approach that could potentially isolate the nuclear spin system completely from the electronic environment.

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Liang Jiang, M. V. Gurudev Dutt, Emre Togan, Lily Childress, Paola Cappellaro, Jacob M. Taylor, Mikhail D. Lukin. 2008-02-20. Coherence of an optically illuminated single nuclear spin qubit. https://doi.org/10.1103/physrevlett.100.073001

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